531 research outputs found

    Hepatitis C Diagnoses in an American Indian Primary Care Population

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    BACKGROUND: Despite large disparities in the burden of chronic liver disease, data on hepatitis C virus (HCV) infection among American Indians (AIs) are lacking. We reviewed hepatitis C diagnoses in 35,712 AI/AN primary care patients. MAIN FINDINGS: At least one HCV-associated ICD-9 code was recorded in 251 (1%) patients between October 1, 2001 and September 30, 2003. An HCV enzyme-linked immunoassay (HCVEIA) was sent in 209 (83.0%); 206/209 (99%) were positive. Confirmatory testing was performed in 144/206 (70%) HCV-EIA positive patients; HCV infection was confirmed in 144 (100%). In the 90/144 (63%) charts with risk factor documentation, injection drug use was the most common risk factor (61/90, 68%). Deficiencies were present in hepatitis B and HIV testing, and hepatitis A and B vaccination. PRINCIPAL CONCLUSIONS: Improvements in laboratory workup of HCV and co-infections, risk factor ascertainment and documentation, and adult vaccination are needed to address HCV effectively in this population

    A comparison of the results of dynamic wind-tunnel tests with theoretical predictions for an aeromechanical gust-alleviation system for light airplanes

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    Dynamic wind tunnel tests have been conducted on a 1/6-scale model of a general aviation airplane equipped with an all-mechanical gust alleviation system which uses auxiliary aerodynamic surfaces to drive the flaps. The longitudinal short period motions were studied under simulated gust conditions in order to verify the mathematical model used in a previous study to predict the performance of the full scale system and determine the amount of normal acceleration alleviation which could be attained. The model responses were measured for different configurations with the system active and without the system active for comparison. The tests confirmed the general relationships between the experimental variables and the model responses predicted by the mathematical model, but there were significant differences in the magnitudes of the responses. The experimental results for the model were used to estimate a reduction of 30 percent in the rms normal acceleration response of a similar full scale airplane in atmospheric turbulence

    Evaluation of a wind-tunnel gust response technique including correlations with analytical and flight test results

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    A wind tunnel technique for obtaining gust frequency response functions for use in predicting the response of flexible aircraft to atmospheric turbulence is evaluated. The tunnel test results for a dynamically scaled cable supported aeroelastic model are compared with analytical and flight data. The wind tunnel technique, which employs oscillating vanes in the tunnel throat section to generate a sinusoidally varying flow field around the model, was evaluated by use of a 1/30 scale model of the B-52E airplane. Correlation between the wind tunnel results, flight test results, and analytical predictions for response in the short period and wing first elastic modes of motion are presented

    Computer Programs for Calculating and Plotting the Stability Characteristics of a Balloon Tethered in a Wind

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    Computer programs for calculating the stability characteristics of a balloon tethered in a steady wind are presented. Equilibrium conditions, characteristic roots, and modal ratios are calculated for a range of discrete values of velocity for a fixed tether-line length. Separate programs are used: (1) to calculate longitudinal stability characteristics, (2) to calculate lateral stability characteristics, (3) to plot the characteristic roots versus velocity, (4) to plot the characteristic roots in root-locus form, (5) to plot the longitudinal modes of motion, and (6) to plot the lateral modes for motion. The basic equations, program listings, and the input and output data for sample cases are presented, with a brief discussion of the overall operation and limitations. The programs are based on a linearized, stability-derivative type of analysis, including balloon aerodynamics, apparent mass, buoyancy effects, and static forces which result from the tether line

    Microprocessor-based Pressure Controller

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    A device for automatic control of pressure in an ion-atom scattering experiment has been constructed. The system was modeled to achieve the minimum time for transition from one pressure to another. The pressure controller learns the system response and iterates the parameters used in profiling the valve voltage to reduce the transition time. The device has been used with two different scattering chambers and has worked well with both

    Reactive Scattering Cell For Atomic Hydrogen And Deuterium

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    A design for a high-temperature reactive scattering cell for atomic hydrogen and atomic deuterium is described. At approximately 2700 K a dissociation of the molecular target species of over 95% has been obtained. The lifetime of 340 h of operation is sufficient for precision, long-time, differential cross-section measurements

    Patient And Provider Characteristics And Practice Patterns of Primary Care Physicians Of Weight-Related Counseling

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    Background: The United States Preventive Services Task Force (USPSTF) recommends three types of health education counseling for use in primary care practices for adult, obese patients. While these recommendations are well known, a low percentage of physicians provide this counseling to their patients on a consistent basis. There are inconsistencies in past studies in regards to what aspects of the health encounter influence the likelihood of receiving health education counseling during a primary care visit. The objective of this study was to (1) investigate the patterns of these three types of counseling occurring within primary care practices and to (2) investigate the influence of patient and provider characteristics on counseling within primary care practices. Methods: We analyzed aggregated data from the 2008-2010 National Ambulatory Medical Care Survey (NAMCS). The three types of health education counseling were the dependent variables, while patient and provider characteristics were the independent variables. Results: Of the 11,041 obese patients seen, 70.3% had no type of counseling provided while only 7.6% had all three types of recommended counseling provided. The highest combination of counseling provided was diet/nutrition and exercise counseling, while the lowest combination was exercise and weight reduction counseling. Additionally, the odds of receiving all 3 types of health education counseling are increased for patients when their obesity check box is checked, being seen for a preventive care visit, having Class III obesity, and seen within an urban practice. Conclusion: Although physicians see a vast amount of adult obese patients within primary care practice, health education counseling practices by primary care physicians remains less than optimal. Therefore, there is a drastic need to improve this type of health education counseling by primary care physicians in order to address the current obesity epidemic in the U.S

    Results of Universal Prenatal Screening for Hepatitis C Infection in a Remote American Indian Primary Care Population

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    BACKGROUND: Although chronic liver disease remains a major area of health disparity for American Indian (AI) people, the epidemiology of hepatitis C virus (HCV) infection among AI people is poorly documented. Because of suspected high local prevalence, two remote AI clinics in the Northern Plains implemented universal prenatal HCV screening in 2005. When this screening program reported an unexpectedly high prenatal anti-HCV (anti-HCV antibody) positivity rate, we conducted a case-control study to determine risks for infection and opportunities for community intervention. MAIN FINDINGS: The clinics screened a total of 205 pregnant women (median age, 22 years). Of these 205 women, a total of 13 (6.3%; 95% confidence interval, 3.4–10.6) had anti-HCV confirmed. Of the anti-HCV-positive women, 10 (76.9%) were aged 15–24 years. We included 10 cases and 40 anti-HCV-negative prenatal controls in a case-control study. On multivariate analysis, only injection-drug use (IDU) remained associated with HCV seropositivity. CONCLUSIONS: Universal prenatal screening revealed a high prevalence of anti-HCV at these remote AI clinics. This population has not been previously described at being at elevated risk for HCV infection. In order to reduce health disparities, young, rural AI populations seeking prenatal care need to be included in interventions to reduce HCV transmission

    Integrating Viral Hepatitis Screening and Prevention Services into an Urban Chemical Dependency Treatment Facility for American Indians and Alaska Natives

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    American Indian/Alaska Natives (AI/AN) patients at an urban residential chemical dependency treatment center participated in a viral hepatitis prevention project. Project activities integrated into patients’ treatment programs included viral hepatitis and human immunodeficiency virus (HIV) risk factor screening, education and counseling, laboratory testing, and hepatitis A and B vaccination. Of 928 AI/AN admissions, 585 (63%) completed risk factor screening assessment. Of these, 436 (75%) received at least one vaccination, viral hepatitis testing, or both. Of 322 patients tested, 91 (28%) were hepatitis C virus (HCV) antibody positive. Lack of pre-existing immunity to vaccine-preventable viral hepatitis infection was common: 132 (45%) were susceptible to hepatitis A and 224 (70%) were susceptible to hepatitis B infection. Chemical dependency treatment centers serving urban AI/AN provide important opportunities for implementing viral hepatitis prevention programs for high-risk populations and for improving ongoing efforts to reduce the disparate impact of chronic liver disease in AI/ AN people
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